CVE-2026-25390: New User Approve Auth Bypass Vulnerability

CVE-2026-25390 Overview

CVE-2026-25390 is a Missing Authorization vulnerability in the New User Approve WordPress plugin developed by Saad Iqbal. This security flaw allows attackers to exploit incorrectly configured access control security levels, potentially enabling unauthorized users to perform administrative actions related to user approval workflows. The vulnerability stems from inadequate authorization checks within the plugin's core functionality.

Critical Impact

Authenticated attackers with low privileges can bypass authorization controls and manipulate user approval processes, potentially granting or denying access to new user registrations without proper administrative permissions.

Affected Products

• New User Approve WordPress Plugin versions up to and including 3.2.3
• WordPress sites utilizing the new-user-approve plugin for user registration management
• Any WordPress installation with vulnerable versions of the plugin active

Discovery Timeline

• 2026-03-25 - CVE-2026-25390 published to NVD
• 2026-03-26 - Last updated in NVD database

Technical Details for CVE-2026-25390

Vulnerability Analysis

This vulnerability falls under CWE-862 (Missing Authorization), indicating that the New User Approve plugin fails to properly verify that a user has the necessary permissions before allowing access to sensitive functionality. The plugin is designed to give administrators control over new user registrations by requiring manual approval before accounts become active. However, the broken access control allows authenticated users with minimal privileges to interact with user approval functions that should be restricted to administrators only.

The attack can be conducted remotely over the network without requiring user interaction. An attacker needs only low-level authenticated access (such as a subscriber role) to exploit this vulnerability. While the confidentiality of data is not directly impacted, the integrity of the user management system can be significantly compromised.

Root Cause

The root cause of CVE-2026-25390 is the absence of proper capability checks or nonce verification in critical plugin functions that handle user approval and denial actions. WordPress plugins should implement robust authorization using functions like current_user_can() to verify that the requesting user possesses appropriate capabilities (such as manage_options or a custom capability) before processing sensitive requests. The vulnerable versions of New User Approve fail to implement these checks adequately, allowing any authenticated user to invoke privileged functionality.

Attack Vector

The vulnerability is exploitable via network access by any authenticated user on a WordPress site running the vulnerable plugin. An attacker would:

1. Obtain any level of authenticated access to the WordPress site (even a subscriber account)
2. Identify or craft requests to the plugin's user approval/denial endpoints
3. Submit requests to approve or deny pending user registrations without having administrator privileges
4. Potentially approve malicious accounts or deny legitimate user registrations

The attack does not require any special conditions or user interaction beyond the initial authentication. The exploitation mechanism involves directly accessing plugin AJAX handlers or form endpoints that lack proper authorization verification. For detailed technical information, refer to the Patchstack Vulnerability Report.

Detection Methods for CVE-2026-25390

Indicators of Compromise

• Unexpected changes in user approval status without corresponding administrator activity
• Audit log entries showing user approval/denial actions from non-administrator accounts
• New user accounts appearing as approved without administrator intervention
• Legitimate pending user registrations being denied without administrator action

Detection Strategies

• Monitor WordPress audit logs for user approval actions performed by non-administrator roles
• Implement Web Application Firewall (WAF) rules to detect and block unauthorized requests to the New User Approve plugin endpoints
• Review user account status changes and correlate with administrator session activity
• Deploy endpoint protection that monitors for anomalous WordPress plugin activity patterns

Monitoring Recommendations

• Enable comprehensive logging of all user management actions within WordPress
• Set up alerts for any user approval/denial activity originating from accounts without administrator capabilities
• Regularly audit the list of approved users against expected registration workflows
• Monitor network traffic to plugin-specific AJAX endpoints for suspicious patterns

How to Mitigate CVE-2026-25390

Immediate Actions Required

• Update the New User Approve plugin to a patched version when available from the plugin author
• Temporarily disable the New User Approve plugin if no patch is available and the functionality is not critical
• Restrict authenticated access to your WordPress site to only trusted users until patched
• Review and audit all recently approved or denied user registrations for unauthorized changes

Patch Information

Organizations should monitor the Patchstack Vulnerability Report for updates on patch availability. Update the New User Approve plugin to a version higher than 3.2.3 once a security fix is released by the plugin maintainer. Ensure automatic plugin updates are enabled for security patches or establish a process for rapid manual updates.

Workarounds

• Temporarily deactivate the New User Approve plugin until a patched version is available
• Implement server-level access controls to restrict access to plugin endpoints to administrator IP addresses only
• Use a WordPress security plugin with WAF capabilities to create custom rules blocking unauthorized requests to the plugin's AJAX handlers
• Consider switching to an alternative user approval plugin that is not affected by this vulnerability

# Temporarily disable the vulnerable plugin via WP-CLI
wp plugin deactivate new-user-approve

# Verify the plugin is deactivated
wp plugin status new-user-approve

# Once a patched version is available, update the plugin
wp plugin update new-user-approve

# Re-enable the plugin after patching
wp plugin activate new-user-approve